nRF documentation warning fixes

embassy-usb/src/builder.rs

@@ -10,6 +10,7 @@ use crate::{Interface, STRING_INDEX_CUSTOM_START};
 #[derive(Debug, Copy, Clone)]
 #[cfg_attr(feature = "defmt", derive(defmt::Format))]
 #[non_exhaustive]
+/// Configuration used when creating [UsbDevice].
 pub struct Config<'a> {
     pub(crate) vendor_id: u16,
     pub(crate) product_id: u16,
@@ -96,6 +97,7 @@ pub struct Config<'a> {
 }
 
 impl<'a> Config<'a> {
+    /// Create default configuration with the provided vid and pid values.
     pub fn new(vid: u16, pid: u16) -> Self {
         Self {
             device_class: 0x00,